Electrical interconnect using locally conductive adhesive

ABSTRACT

An anisotropic electrically conducting interconnect is disclosed in which an adhesive comprising particles having a breakable coating of at feast one electrically nonconductive material is compressed between a first contact and a second contact. Compression to two contacts breaks the breakable coating exposing an electrically conducting material which makes contact with the first and second contacts. The electrically conducting material may be a metal conductor or a two-part reactive conductive resin/catalyst system. Also disclosed are processes for making such electrical interconnects and adhesives for use in making electrical interconnect.

CROSS-REFERENCE TO RELATED U.S. APPLICATIONS

[0001] This application is a Divisional of co-pending U.S. applicationSer. No. 10/132,835, filed Apr. 25, 2002 incorporated by referenceherein.

BACKGROUND OF THE INVENTION

[0002] This invention relates generally to semiconductors, and morespecifically to methods and apparatus for making anisotropic electricalinterconnects.

[0003] Anisotropic electrical interconnects are known in the art. U.S.Pat. No. 6,194,492 B1 discloses an anisotropic conductive film whichexhibits a conductivity in the thickness direction thereof bypressurizing the film in the thickness direction, the film including: anadhesive; and conductive particles dispersed in the adhesive; whereinthe adhesive is a thermosetting or photosetting adhesive containing as amain component at least one kind selected from a group consisting of (a)a polymer obtained by acetalation of a polyvinyl alcohol, (b) a compoundcontaining an allyl group, (c) a monomer containing an acryloxy group ormethacryloxy group, and (d) a polymer obtained by polymerization of oneor more selected from a group consisting of an acrylic monomer and amethacrylic monomer.

[0004] U.S. Pat. No. 5,932,339 discloses an anisotropicallyelectricity-conductive film obtainable by dispersing in an adhesiveagent electrically conductive particles, the adhesive agent being acurable adhesive agent comprising as a major component at least onepolymer selected from the group consisting of an ethylene-vinyl acetatecopolymer; a copolymer of ethylene, vinyl acetate and an acrylate and/ormethacrylate monomer; a copolymer of ethylene, vinyl acetate and maleicacid and/or maleic anhydride; a copolymer of ethylene, an acrylateand/or methacrylate monomer and maleic acid and/or maleic anhydride; andan ionomer resin wherein molecules of an ethylene-methacrylic acidcopolymer are linked with each other through a metal ion.

[0005] U.S. Pat. No. 5,865,703 discloses an anisotropic, electricallyconductive adhesive film including insulating adhesive, electricallyconductive particles dispersed in the electrically insulating adhesive,and transparent, spherical glass particles dispersed in the insulatingadhesive.

[0006] U.S. Pat. No. 5,162,087 discloses an anisotropic conductiveadhesive composition comprising an insulating adhesive component andparticles dispersed in said insulating adhesive component, saidanisotropic conductive adhesive composition being characterized in thatsaid insulating adhesive component comprises a copolymer of acrylicester having an alkyl group of 1-4 carbon atoms and a maleimidederivative, 5 to 60 parts by weight, based on 100 parts by weight of thecopolymer, of a thermosetting resin, and 0.05 to 5.0 parts by weight,based on 100 parts by weight of the copolymer, of a coupling agent, andsaid particles are metallic-layer containing particles comprising a coremade of resin, a metallic layer covering said core and a resin layerformed from finely divided resin fixed by the dry blending method on thesurface of said metallic layer.

[0007] U.S. Pat. No. 4,740,657 discloses an adhesive composition or filmcapable of exhibiting anisotropic-electroconductivity comprisingelectroconductive particles comprising polymeric core materials coatedwith thin metal layers, and electrically insulating adhesive component.

[0008] U.S. Pat. No. 5,965,064 discloses an anisotropicallyelectroconductive adhesive to be used for establishing electricconnection between terminals of, for example, an IC chip and of acircuit pattern, which adhesive comprises an electrically insulatingadhesive matrix and electroconductive particles comprise at least twoelectroconductive particulate products of different average particlesizes and wherein each particle of both the particulate products iscoated with an electrically insulating resin insoluble in the insulatingadhesive matrix.

[0009] U.S. Pat. No. 5,302,456 discloses an anisotropic conductivematerial including micro-capsules dispersed in a bonding resin. Themicro-capsules contain, as a filler material, a conductor and apolymerization initiator, a curing agent or a curing promotor. A wallmember encapsulating the filler material is formed of a thermoplastic orthermosetting insulative resin. Therefore, if the micro-capsules in theanisotropic conductive material are broken or destroyed by pressure orboth of pressure and heat, electrical connection can be establishedbetween electrode pads and electrode terminals of a wiring substratethrough the conductors contained in the micro-capsules. Simultaneously,the polymerization initiator, the curing agent or the curing promotorflows out, so that the insulative bonding resin is solidified.

[0010] The above prior art typically achieves the anisotropic effect bycontrolling filler loading. In other words, to obtain an anisotropicinterconnect the adhesive must use few particles. However, these priorart methods still have serious leakage problems if the filler loading istoo high or too uneven. The filler loading is hard to control especiallyif the filler responds to gravity or magnetic fields.

BRIEF SUMMARY OF THE INVENTION

[0011] In one preferred embodiment, the invention is an electricalinterconnect comprising (a) at least one first electrical contact; (b)at least one second electrical contact; and, (c) an adhesive interposedbetween and in contact with the first electrical contact and the secondelectrical contact, the adhesive comprising an electricallynon-conductive resin and particles, the particles comprising at leastone electrically conductive material and a breakable coating of at leastone electrically non-conductive material, wherein the first electricalcontact is positioned close enough to the second electrical contact tobreak the breakable coating of the particles in the interposed adhesivesuch that the electrically conducting material of the particles isexposed and in contact with both the first electrical contact and thesecond electrical contact, wherein the exposed electrically conductingmaterial has sharp edges. This embodiment includes semiconductor dies orchips and semiconductor packages comprising such an interconnect.

[0012] In another preferred embodiment, the invention is an electricalinterconnect comprising: (a) a first substrate having a surface and atleast one first electrical contact projecting from the first substratesurface; (b) a second substrate having a surface and at least one secondelectrical contact projecting from the second substrate surface andaligned with the first electrical contact, such that the first substratesurface is substantially parallel to the second substrate surface; and,(c) an adhesive interposed between and in contact with the firstsubstrate surface and electrical contact and the second substratesurface and electrical contact, the adhesive comprising an electricallynon-conductive resin and particles, the particles comprising a core ofat least one electrically conductive material and a breakable coating ofat least one electrically non-conductive material, wherein the firstelectrical contact is positioned close enough to the second electricalcontact to break the breakable coating material of the particles in theadhesive interposed between the first electrical contact and the secondelectrical contact such that the electrically conducting material of theparticles is exposed and in contact with both the first electricalcontact and the second electrical contact, wherein the exposedelectrically conducting material has sharp edges, provided that thecoating of the particles interposed between the first substrate surfaceand the second substrate surface, but not interposed between the firstelectrical contact and the second electrical contact, is not broken.This embodiment includes semiconductor dies or chips and semiconductorpackages comprising such an interconnect.

[0013] In another preferred embodiment, the invention is an electricalinterconnect comprising: (a) at least one first electrical contact; (b)at least one second electrical contact; and, (c) an adhesive interposedbetween and in contact with the first electrical contact and the secondelectrical contact, the adhesive comprising an electricallynon-conductive resin and particles, the particles comprising a core ofat least one electrically conductive reactive material and a breakablecoating of at least one electrically non-conductive material, the corecomprising: (1) at least one first subparticle comprising a reactiveresin, having conductive material therein, encapsulated inside arupturable membrane; and, (2) at least one second subparticle comprisinga catalyst encapsulated inside a rupturable membrane, wherein the firstelectrical contact is positioned close enough to the second electricalcontact to break the breakable coating of the particles in theinterposed adhesive such that the first subparticle membrane and thesecond subparticle membrane are ruptured, whereby the reactive resin andthe catalyst react to form a conductive adhesive between the firstelectrical contact and the second electrical contact. This embodimentincludes semiconductor dies or chips and semiconductor packagescomprising such an interconnect.

[0014] In yet another preferred embodiment, the invention is anelectrical interconnect comprising: (a) a first substrate having asurface and at least one first electrical contact projecting from thefirst substrate surface; (b) a second substrate having a surface and atleast one second electrical contact projecting from the second substratesurface and aligned with the first electrical contact, such that thefirst substrate surface is substantially parallel to the secondsubstrate surface; and, (c) an adhesive interposed between and incontact with the first electrical contact and the second electricalcontact, the adhesive comprising an electrically non-conductive resinand particles, the particles comprising a core of at least oneelectrically conductive reactive material and a breakable coating of atleast one electrically non-conductive material, the core comprising: (1)at least one first subparticle comprising a reactive resin, havingconductive material therein, encapsulated inside a rupturable membrane;and, (2) at least one second subparticle comprising a catalystencapsulated inside a rupturable membrane, wherein the first electricalcontact is positioned close enough to the second electrical contact tobreak the breakable coating of the particles in the interposed adhesivesuch that the first subparticle membrane and the second subparticlemembrane are ruptured, whereby the reactive resin and the catalyst reactto form a conductive adhesive between the first electrical contact andthe second electrical contact provided that the coating of the particlesinterposed between the first substrate surface and the second substratesurface, but not interposed between the first electrical contact and thesecond electrical contact, is not broken. This embodiment includessemiconductor dies or chips and semiconductor packages comprising suchan interconnect.

[0015] In yet another preferred embodiment, the invention is anelectrical interconnect comprising: (a) at least one first electricalcontact; (b) at least one second electrical contact; and, (c) anadhesive interposed between and in contact with the first electricalcontact and the second electrical contact, the adhesive comprising: (1)an electrically non-conductive resin; (2) multiple first particles, eachfirst particle comprising a core comprising at least one reactive resin,having an electrically conductive material therein, and a breakablecoating of at least one electrically non-conductive material; and (3)multiple second particles, each second particle comprising a corecomprising a catalyst and a breakable coating of at least oneelectrically non-conductive material, wherein the first electricalcontact is positioned close enough to the second electrical contact tobreak the breakable coatings of the first particles and the secondparticles in the interposed adhesive, whereby the reactive resin and thecatalyst react to form a conductive adhesive between the firstelectrical contact and the second electrical contact. This embodimentincludes semiconductor dies or chips and semiconductor packagescomprising such an interconnect.

[0016] In another preferred embodiment, the invention is an electricalinterconnect comprising: (a) a first substrate having a surface and atleast one first electrical contact projecting from the first substratesurface; (b) a second substrate having a surface and at least one secondelectrical contact projecting from the second substrate surface andaligned with the first electrical contact, such that the first substratesurface is substantially parallel to the second substrate surface; and,(c) an adhesive interposed between and in contact with the firstelectrical contact and the second electrical contact, the adhesivecomprising: (1) an electrically non-conductive resin; (2) multiple firstparticles, each first particle comprising a core comprising at least onereactive resin, having an electrically conductive material therein, anda breakable coating of at least one electrically non-conductivematerial; and (3) multiple second particles, each second particlecomprising a core comprising a catalyst and a breakable coating of atleast one electrically non-conductive material, wherein the firstelectrical contact is positioned close enough to the second electricalcontact to break the breakable coatings of the first particles and thesecond particles in the interposed adhesive, whereby the reactive resinand the catalyst react to form a conductive adhesive between the firstelectrical contact and the second electrical contact, contact providedthat the coating of the particles interposed between the first substratesurface and the second substrate surface, but not interposed between thefirst electrical contact and the second electrical contact, is notbroken. This embodiment includes semiconductor dies or chips andsemiconductor packages comprising such an interconnect.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Preferred embodiments of the invention are described below withreference to the following accompanying drawings, which are forillustrative purposes only. Throughout the following views, referencenumerals will be used in the drawings, and the same reference numeralswill be used throughout the several views and in the description toindicate same or like parts.

[0018]FIG. 1 is a schematic view of one embodiment of the apparatus ofthe invention prior to the formation of the interconnect.

[0019]FIG. 2 is a cross-sectional view of a particle of FIG. 1.

[0020]FIG. 3 is a schematic view of the apparatus of FIG. 1 at aprocessing step subsequent to forming the interconnect.

[0021]FIG. 4 is a schematic view of one embodiment of the apparatus ofthe invention prior to the formation of the interconnect.

[0022]FIG. 5 is a cross-sectional view of a particle of FIG. 4.

[0023]FIG. 6 is a schematic view of the apparatus of FIG. 4 at aprocessing step subsequent to forming the interconnect.

[0024]FIG. 7 is a schematic cross-section view of one embodiment of theapparatus of the invention prior to the formation of the interconnect.

[0025]FIG. 8 is a schematic cross-section view of the apparatus of FIG.7 at a processing step subsequent to forming the interconnect.

DETAILED DESCRIPTION OF THE INVENTION

[0026] In the following detailed description, references made to theaccompanying drawings which form a part hereof, and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it is tobe understood that other embodiments may be utilized and that electricalchanges may be made without departing from the spirit and scope of thepresent invention.

[0027] The terms “wafer” or “substrate” used in the followingdescription include any semiconductor-based structure having a siliconsurface. Wafer and substrate are to be understood as includingsilicon-on-insulator (SOI) or silicon-on-sapphire (SOS) technology,doped and undoped semiconductors, epitaxial layers of silicon supportedby a base semiconductor foundation, and other semiconductor structures.Furthermore, when references made to a wafer or substrate in thefollowing description, previous process steps may have been used to formregions or junctions in the base semiconductor structure or foundation.Preferred substrates are semiconductor structures such as semiconductordies, semiconductor chips and semiconductor packages.

[0028]FIG. 1 shows a step of a preferred process for making oneembodiment of the inventive electric interconnect. A first substrate 1having a first electrical contact 3 is positioned opposite a secondsubstrate 5 having a second electrical contact 7. The first substrate 1and the second substrate 5 are positioned relative to each other suchthat the first electrical contact 3 is aligned with the secondelectrical contact 7. An adhesive 9 is interposed between the firstelectrical contact 3 and the second electrical contact 7. The adhesive 9comprises particles 11.

[0029] The adhesive 9 may be any insulating adhesive resin usable in theart. Such adhesives resins are described in U.S. Pat. No. 5,336,443,incorporated herein by reference, and include ethylene-vinyl acetatecopolymeric resins unmodified or modified with carboxyl groups,copolymers of ethylene with methyl, ethyl or isobutyl acrylate,polyamide resins, polyester resins, poly(methyl methacrylate) resins,poly(vinyl ether) resins, poly(vinyl butyral) resins, polyurethaneresins, styrene-butadiene-styrene block copolymers unmodified ormodified with carboxyl groups, styrene-isoprene-styrene copolymericresins, styrene-ethylene-butylene-styrene copolymers unmodified ormodified with maleic acid, polybutadiene rubbers, polychloroprenerubbers unmodified or modified with carboxyl groups, styrene-butadienecopolymeric rubbers, isoprene-isobutylene copolymers, nitrile rubbersmodified with carboxyl groups, epoxy resins, silicone resins and thelike. These polymeric materials can be used either singly or as acombination of two kinds or more according to need.

[0030] It is optional that the above named adhesive polymeric materialis admixed with a tackifier such as rosins and derivatives thereof,terpene resins, terpene-phenol copolymeric resins, petroleum resins,coumarone-indene resins, styrene-based resins, isoprene-based resins,phenolic resins, alkylphenol resins and the like either singly or as acombination of two kinds or more.

[0031] Further, the adhesive resin can optionally be admixed withvarious kinds of known additives including reaction aids, catalysts, orcross-linking agents such as phenolic resins, polyol compounds,isocyanate compounds, melamine resins, urea resins, urotropinecompounds, amine compounds, acid anhydrides, organic peroxides, metaloxides, metal salts of an organic acid, e.g., chromium trifluoroacetate,alkoxides of a metal, e.g., titanium, zirconium and aluminum, andorganometallic compounds, e.g., dibutyltin oxide, as well asphotopolymerization initiators, e.g., 2,2-diethoxy acetophenone andbenzil, sensitizer, e.g., amine compounds, phosphorus compounds andchlorine compounds, and so on. The adhesive 9 is preferably in the formof a film or a paste.

[0032] Preferably, the adhesive resin does not expand when cured, morepreferably, the adhesive resin shrinks during cure.

[0033] The adhesive 9 may be positioned to interpose the two substratesbefore the first substrate 1 and the second substrate 5 are aligned inrelation to each other. For example, the adhesive 9 may be depositedover the surface of one of the substrates followed by positioning theother substrate.

[0034]FIG. 2 shows a cross-sectional view of one embodiment of particle11. Typically, the particles 11 are generally rounded in shape,preferably spherical. Particles 11 typically have an average diameter ofbetween about 0.5 ∥ to about 100 μ. The particle 11 has a core 13 of anelectrically conductive material, or a material that can react to forman electrically conductive material, surrounded by a breakable coating15 of an electrically non-conducting material. Optionally, the core maybe pre-broken to form fracture lines 17. The pre-broken core can beformed by thermally or chemically stressing the core. A pre-broken coremay also be formed as an agglomeration of fragments.

[0035] In one preferred embodiment, the core 13 comprises any metal thatwill form sharp edges when fractured. The metal is preferably nickel,copper, silver or molybdenum. The metal can also be a metal thatoxidizes in the presence of oxygen because the metal is in a controlledenvironment in the interconnect. The metal is preferably pre-cracked inorder to facilitate the formation of sharp edges and surfaces on themetal when the particle is broken by compression. The sharp edges andsurfaces ensure contact between the contact surfaces.

[0036] The breakable electrically non-conductive coating can be anyappropriate material that can hold the conductive material togetheruntil the particles are broken by compression between the contacts.Examples of suitable electrically non-conductive materials includepolymer resins and ceramics. A suitable ceramic is alumina oxide.

[0037]FIG. 3 shows the process after the interconnect has been formed.The first substrate 1 and the second substrate 5 have been repositionedcloser to each other to compress the adhesive 9. In particular, the twosubstrates have been repositioned such that the electrically conductingparticles 11 are compressed and broken between the first contact 3 andthe second contact 7. The broken particles 19 preferably have sharpedges 21 to enhance the electrical connection between the brokenparticles 19 and the contacts. The broken particles 19 typically have anaverage largest dimension of about 0.1 ∥ to about 20 μ. The particles 11in adhesive 9 which are not located between the contacts are notsubjected to enough compression to break the coating on those particles.As such, an electrical connection is formed between the first contact 3and the second contact 7 but the adhesive 9 and particles 11 not locatedbetween the two contacts remain non-electroconductive.

[0038]FIG. 4 shows a step of this process for making another preferredembodiment the inventive electric interconnect. A first substrate 101having a first electrical contact 103 is positioned opposite a secondsubstrate 105 having a second electrical contact 107. The firstsubstrate 101 and the second substrate 105 are positioned relative toeach other such that the first electrical contact 103 is aligned withthe second electrical contact 107. An adhesive 109 is interposed betweenthe first electrical contact 103 and the second electrical contact 107.The adhesive 109 comprises particles 111.

[0039] The adhesive 109 may be any insulating adhesive resin usable inthe art as described above. The adhesive 109 is preferably in the formof a film or a paste.

[0040] The adhesive 109 may be positioned to interpose the twosubstrates before the first substrate 101 and the second substrate 105are aligned in relation to each other. For example, the adhesive 109 maybe deposited over the surface of one of the substrates followed bypositioning the other substrate.

[0041]FIG. 5 shows a cross-sectional view of the particle 111.Typically, the particles 111 are generally rounded in shape, preferablyspherical. The particle 111 has a core 113 of a material that can reactto form an electrically conductive material, surrounded by a breakablecoating 115 of an electrically non-conducting material. Particle 111typically has an average diameter of about 0.5 μ to up to about 250 μ.

[0042] Core 113 comprises a multiplicity of first subparticles 117 andsecond subparticles 123. First subparticles 117 comprise a rupturablemembrane 119 and a reactive resin 121 which is electrically conductive.Rupturable membrane 119 may be made of any suitable organic material,for example, polymer resins insoluble in reactive resin 121. Reactiveresin 121 can comprise any resin usable for adhesive 109, preferably anepoxy resin. Reactive resin 121 is rendered electrically conductivethrough filling with chunks of electrically conductive materials such assilver, nickel, copper, molybdenum. Second subparticle 123 comprises arupturable membrane 125 and a catalyst 127 enclosed therein. Rupturablemembrane 125 may be any suitable organic material that is insoluble incatalyst 127, preferably a polymer resin. Catalyst 127 is selected toreact with reactive resin 121 to form a cured adhesive.

[0043] The breakable electrically non-conductive coating 115 can be anyappropriate material that can hold the conductive material togetheruntil the particles are broken by compression between the contacts.Examples of suitable electrically non-conductive materials includepolymer resins and ceramics. A suitable ceramic is alumina oxide.

[0044]FIG. 6 shows the process after the interconnect has been formed.The first substrate 101 and the second substrate 105 have beenrepositioned closer to each other to compress the adhesive 109. Inparticular, the two substrates have been repositioned such that theparticles 111 are compressed and broken between the first contact 103and the second contact 107.

[0045] When particles 111 are compressed and broken, membranes 119 offirst subparticles 117 and 125 of second subparticle 123 are rupturedpermitting reactive resin 121 and catalyst 127 to intermingle and react.As a result, a cured adhesive bond is formed between first contact 103and second contact 107 wherein the adhesive is electrically conductive.

[0046]FIG. 7 shows a cross-sectional view of a process for making oneembodiment of the inventive electric interconnect. A first substrate 201having a first electrical contact 203 is positioned opposite a secondsubstrate 205 having a second electrical contact 207. The firstsubstrate 201 and the second substrate 205 are positioned relative toeach other such that the first electrical contact 203 is aligned withthe second electrical contact 207. An adhesive 209 is interposed betweenthe first electrical contact 203 and the second electrical contact 207.The adhesive 209 comprises first particles 211 and second particles 217.

[0047] The adhesive 209 may be any insulating adhesive resin usable inthe art as described above. The adhesive 209 is preferably in the formof a film or a paste.

[0048] The adhesive 209 may be positioned to interpose the twosubstrates before the first substrate 201 and the second substrate 205are aligned in relation to each other. For example, the adhesive 209 maybe deposited over the surface of one of the substrates followed bypositioning the other substrate.

[0049] First particle 211 comprises a conductive resin 215 containedwithin a breakable coating 213 of an electrically nonconductingmaterial. Conductive resin 215 comprises one-half of a two-partadhesive, preferably an epoxy resin, filled with electrically conductingmaterial. The electrically conducting material is preferably silver butmay also be nickel, copper or molybdenum. The breakable electricallynon-conductive coating 215 can be any appropriate material that can holdthe conductive material together until the particles are broken bycompression between the contacts. Examples of suitable electricallynon-conductive materials include polymer resins and ceramics. A suitableceramic is alumina oxide.

[0050] Second particle 217 comprises a catalyst 221 encased within abreakable coating 219 made from an electrically nonconducting material.The catalyst 221 is selected to react with the conductive resin 215 asthe other component of the two-part adhesive, preferably an epoxy resin.The breakable electrically non-conductive coating 219 can be anyappropriate material that can hold the conductive material togetheruntil the particles are broken by compression between the contacts.Examples of suitable electrically non-conductive materials includepolymer resins and ceramics. A suitable ceramic is alumina oxide.

[0051]FIG. 8 shows the process after the interconnect has been formed.The first substrate 201 and the second substrate 205 have beenrepositioned closer to each other to compress the adhesive 209. Inparticular, the two substrates have been repositioned such that theparticles 211 and the second particles 217 are compressed and brokenbetween the first contact 203 and the second contact 207. The conductiveresin 215 from broken first particles 211 intermingles with and reactswith the catalyst 221 from broken second particles 217. The reaction ofconductive resin 215 with catalyst 221 results in a cured adhesive 223.First particles 211 and second particles 217 which are not locatedbetween first contact 203 and second contact 207 are not broken in thecompression step.

[0052] The electrical interconnect of the current invention is usablefor any interconnection between two semiconductor parts each having acontact. In particular, the inventive interconnect is usable onsemiconductor dies, chips or package. The inventive adhesive couldreplace solder paste in forming interconnects with die, chips andpackages. The inventive adhesive can also be used as a surface mountmaterial.

[0053] In compliance with the statute, the invention has been describedin language more or less specific as to structural and methodicalfeatures. It is to be understood, however, that the invention is notlimited to the specific features shown and described, since the meansherein disclosed comprise preferred forms of putting the invention intoeffect. The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

What is claimed is:
 1. A process for preparing an electricalinterconnect, the process comprising the steps of: (a) providing a firstsubstrate having a surface and at least one first electrical contactprojecting from the first substrate surface; (b) positioning a secondsubstrate, having a surface and at least one second electrical contactprojecting from the second substrate surface, opposite to the firstsubstrate such that the first substrate surface is substantiallyparallel with the second substrate surface and the first electricalcontact is aligned with the second electrical contact; (c) positioningan adhesive between: (i) the first substrate surface and firstelectrical contact projecting therefrom and (ii) the second substratesurface and second electrical contact therefrom, the adhesive comprisingparticles, the particles comprising at least one electrically conductivematerial coated with at least one electrically non-conductive material;(d) moving the at least one of the first substrate or the secondsubstrate closer to the other such that the first electrical contact ispositioned close enough to the second electrical contact to break theelectrically non-conductive coating material of the particles in theinterposed adhesive such that the electrically conducting material ofthe particles is exposed and in contact with both the first electricalcontact and the second electrical contact.
 2. The process of claim 1wherein the electrically conductive material is selected from the groupconsisting of nickel, silver, copper and molybdenum.
 3. The process ofclaim 1 wherein the electrically conductive material is pre-cracked. 4.The process of claim 3 wherein the electrically conductive material ispre-cracked to a treatment with chemical or thermal stress.
 5. Theprocess of claim 1 wherein the electrically conductive material is anagglomeration of small sharp fragments.
 6. The process of claim 1wherein the adhesive resin does not expand upon curing.
 7. The processof claim 1 wherein the adhesive is in the form of a paste or a film. 8.The process of claim 1 wherein the particle has a average particle sizeof between 0.5 to about 100 microns before being broken.
 9. A processfor preparing an electrical interconnect, the process comprising thesteps of: (a) providing a first substrate having a surface and at leastone first electrical contact projecting from the first substratesurface; (b) positioning a second substrate, having a surface and atleast one second electrical contact projecting from the second substratesurface, opposite to the first substrate such that the first substratesurface is substantially parallel with the second substrate surface andthe first electrical contact is aligned with the second electricalcontact; (c) positioning a first adhesive between: (i) the firstsubstrate surface and first electrical contact projecting therefrom and(ii) the second substrate surface and second electrical contacttherefrom, the first adhesive comprising an electrically non-conductiveresin and particles, the particles comprising a core and a breakablecoating of at least one electrically non-conductive material, the corecomprising: (1) at least one first subparticle comprising a reactiveresin, having conductive material therein, encapsulated inside arupturable membrane; and, (2) at least one second subparticle comprisinga catalyst encapsulated inside a rupturable membrane, (d) moving the atleast one of the first substrate or the second substrate closer to theother such that the first electrical contact is positioned close enoughto the second electrical contact to break the breakable coating of theparticles in the interposed first adhesive such that the firstsubparticle membrane and the second subparticle membrane are ruptured,whereby the reactive resin and the catalyst react to form a conductivesecond adhesive between the first electrical contact and the secondelectrical contact provided that the coating of the particles interposedbetween the first substrate surface and the second substrate surface,but not interposed between the first electrical contact and the secondelectrical contact, is not broken.
 10. The process of claim 9 whereinthe conductive material comprises chunks of a metal selected from thegroup consisting of silver, copper, nickel, and molybdenum.
 11. Theprocess of claim 9 wherein the reactive resin and the catalyst are eachone component of a two part conductive adhesive resin.
 12. The processof claim 1I wherein the conductive second adhesive resin is a two partepoxy.
 13. The process of claim 9 wherein neither the first nor secondadhesive expands upon curing.
 14. The process of claim 9 wherein thefirst adhesive is in the form of a paste or a film.
 15. A process forpreparing an electrical interconnect, the process comprising the stepsof: (a) providing a first substrate having a surface and at least onefirst electrical contact projecting from the first substrate surface;(b) positioning a second substrate, having a surface and at least onesecond electrical contact projecting from the second substrate surface,opposite to the first substrate such that the first substrate surface issubstantially parallel with the second substrate surface and the firstelectrical contact is aligned with the second electrical contact; (c)positioning a first adhesive between: (i) the first substrate surfaceand first electrical contact projecting therefrom and (ii) the secondsubstrate surface and second electrical contact therefrom, the firstadhesive comprising: (1) an electrically non-conductive resin; (2)multiple first particles, each first particle comprising a corecomprising at least one reactive resin, having an electricallyconductive material therein, and a breakable coating of at least oneelectrically non-conductive material; and (3) multiple second particles,each second particle comprising a core comprising a catalyst and abreakable coating of at least one electrically non-conductive material,(d) moving the at least one of the first substrate or the secondsubstrate closer to the other such that the first electrical contact ispositioned close enough to the second electrical contact to break thebreakable coatings of the first particles and the second particles inthe interposed first adhesive, whereby the reactive resin and thecatalyst react to form a conductive second adhesive between the firstelectrical contact and the second electrical contact, contact providedthat the coating of the particles interposed between the first substratesurface and the second substrate surface, but not interposed between thefirst electrical contact and the second electrical contact, is notbroken.
 16. The process of claim 15 wherein the conductive materialcomprises chunks of a metal selected from the group consisting ofsilver, copper, nickel, and molybdenum.
 17. The process of claim 15wherein the reactive resin and the catalyst are each one component of atwo part conductive adhesive resin.
 18. The process of claim 17 whereinthe conductive second adhesive resin is a two part epoxy.
 19. Theprocess of claim 15 wherein neither the first nor second adhesiveexpands upon curing.
 20. The process of claim 15 wherein the firstadhesive is in the form of a paste or a film. in the first adhesive isin the form of a paste or a film.